Right. Cognitive dissonance. We all suffer it sometimes. I guess it takes uncommon courage and clarity to work through it. Most people would rather do the least effort to preserve their sense of being a good person.
Being sexist is bad
They are good
They don't like this show because it has a woman lead
That's sexist
But they're good
Can't change "sexism is bad". Can't change "they are good". Only thing left to change is the reason they don't like the show. Easy-peasy.